Electronic displays of the type used in small handheld electronic devices such as mobile telephones and PDA's are well known. It is known to provide a mobile telephone with a conventional liquid crystal display (LCD) to provide the user with information concerning the status of the telephone and to enable a large number of different functions to be accessed and selected easily.
An LCD is a reflective display which means that there must be at least some ambient light for it to be seen. In situations where the ambient light is too low or in darkness, an LCD cannot be seen at all. For this reason an LCD is often provided with a backlight, such as an array of light emitting diodes (LED's) positioned around the periphery of the display, to illuminate it. An alternative to an array of LED's is an electroluminescent film beneath the display that glows when current is passed through it, thereby illuminating the LCD display from below.
A problem with a conventional display such as an LCD described above is that they suffer from poor contrast and so are difficult or impossible to see easily in well lit environments or in bright sunlight. Even in low light or dark environments, when the display is illuminated using an array of LED's or an electroluminescent film, the contrast of the display is low and readability is poor.
It is an object of the present invention to overcome or substantially alleviate the disadvantages with the conventional displays such as those discussed above and to provide a display that provides a high degree of display legibility in dynamic lighting environments.